The present invention concerns an operative instrument for endoscopic surgery, which is passed through a tubular trocar and is used to perform a surgical procedure, etc. inside a body cavity under endoscopic observation.
In recent years, endoscopic surgery has come to be performed widely for various types of surgery since the interior of the body cavity can be subjected to surgical treatment without large incision. In the endoscopic surgery, several small opened parts are made in the abdominal wall, a tubular trocar is passed through each opened part, and an endoscope is passed through one trocar while various operative instruments are passed through the other trocars.
The use of the trocars prevents damage of the opened part of the abdominal wall in the process of inserting or removing the endoscope and operative instrument, and prevents leakage of air when operative instruments are used interchangeably.
The length of an operative instrument used in the surgery under endoscopic observation is short since it is to be used upon insertion through a trocar. In general, the operative instrument is designed such that manipulating shaft (or manipulating wire) is retractably inserted and positioned in the axial direction in a rigid jacket tube, and a distal end operative member, which is actuated by advancing and retreating the manipulating shaft, is attached to the distal end of the jacket tube.
In case where the rear side of an organ must be subjected to treatment by endoscopic surgery, an operative instrument with a curved jacket tube is used.
Since the operative instrument is used upon being passed through the trocar as abovementioned, a trocar with a curvature which matches the curvature of the jacket tube must be prepared.